Well-screen



' i To all 'whom 'it may concem:

WELL-SCREEN. L

Application mea July 2s; 1919. seriarxvo. 313,723. 'l'

Be it known that I, XVILLIAM H. CATER, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Well-Screens, of which the following is a specification.

My invention pertains to screens or strainy y. ers of various kinds but more particularly concerns features of novelty and improve- -.ment, both from structural and functional standpoints, in well-screens adapted to permit the passage of water therethrough but to hold back sand, dirt, gravel and the like. One leading pbject of the invention is the provision of a tubular screen or strainer of substantial size and strength with a rela tively small or fine mesh. Iloles of the small caliber required fora screen or filter of the fine mesh desired cannot satisfactorily be punched. in sheets of metal. of athickness suilicient to give the tube or pipe adequate strength. A. punch small enough to produce lthe minute holes desired would have inadequate strength to aperform the punching or metal removing operation without breaking. Accordingly, it becomes necessary to use some other expedient to produce the desired result.

In accordance with the principles of this invention in its preferred embodiment a long sheet-metal strip is punched to produce round holes of a size permitted by the thickness of the metal. Owing to the thiclmess or gage of metal needed to produce a tube of `the required strength such round holes are too large to perform by themselves alone the screening or filtering operation. Such sheetmetal strip is'wound up spirally with its longitudinal marginal or edge portions overlapped and riveted or otherwise secured together, thereby forming a hollow, cylindrical, perforated tube or pipue with an exposed, outer, spiral shoulderor le e produced by the edge of the metal sheet.

similarly-arranged, spiral, metal sheet en- ;circling the innen one nd`bearing at one "y tened tothe' inner or underlying thicker metall sheet. elongated ornarrow rectangular openings or slots of finerl mesh than the round holes of the inner sheet and more or less in" register..

Specicati-on of Letters Patent.

this invention and its various benefits and advantages, I have illustrated inthe accomhis spiral tube is provided with'an outer shell comprising a Ving in 'place` the outer, perforated, lnletal Such outer spiral sheet has- WILLIAM n. CATER, oF CHICAGO, xrnnrivors. y

rateteaaune s, ileso.

therewith, the apertures of the surrounding or encircling sheet having their longer axes or d11nens1ons substantially-parallel to the axis of the tube or pipe to facilitate cleaning 3nd to prevent clogging, at least in some e ee.

When a screen or strainenof still ner mesh `1s wanted a spirally-disposed wirecloth or fine-mesh screen (copper or bronze for anstance) is interposed between the twoA apertured or perforated metal sheets, whereby the screen as a whole is composed of these three superposed spirally-arranged screen members or elements, all of different mesh, the liner one being between, held in place by, and-protected from injury or damage by the other two."

In order that those skilled in this art may have` a full and complete understanding of panying drawing, forming a part of this specification, a preferred and desirable embodiment of the invention, the single view of the drawing showing fragmentarily a sect1on of the improved screen or strainer with the parts broken away trate the construction.

As is clearly depicted 'the strainer, screen,

or filter comprises a hollow cylindrical tube or lcaslng composed primarily of a relativelyf long sheet of metal 10, provided with a plurality of round perforations 11, bent or shaped into spiral or helical form with its longitudinal margins or borders overlapped and secured together as by a spiral'row of rivets 12.

The lower edge portion of the sheet at such spiral joint lits inside of the adjacent upper edge portion of another section of the sheet, whereby the tube or pipe internally presents no obstruction to the downward insertion of any member of substantially the diameter of the inner caliber of the pipe. Such helical joint provides an external 'spiral shpulder l3-formed bythe exposed edge of the metal lsheet which is taken advantage of in properly positioning and hold,-

s'heet. ,v

Surrounding this supporting tube or 'shell and bearing against its outenface and of a width* to cover its lnumerous holes is a i spirall -arranged wire-cloth screen 14, desir.- 110l ably o copper, of the.' required lmesh for the l screen as a whole.

to more clearly Pillusl l SI5 v substantially parallel to its axis.

\ shoulder 13 of the thicker metal sheet 1() andv its other or upper border or margin is fas-A ,tened to 'the underlying sheet 10 by a row of rivets 17 or by solder, welding, or otherwise.

It will be perceived that .the strainer or screen as a whole comprises a plurality of spirally-arranged, superposed, reticulated or foraminous-` members or sheets which unitedly or conjointly form a structure of suitable and sufficient strength and of rela tively fine mesh or gage. In some cases where a coarser mesh structure is required,

the intermediate wire-cloth screen 14 may be omitted, the tube or pipe then comprising only the two perforated metal sheets with apertures of different sizes and of metal of different gages.

It will be readily understood that this inventionis not limited andrestricted to any exact measurements of the parts but merely by way of example I might mention that for a pipe or tube twenty inches in diameter the width of the metal strip 10 could conveniently be fifteenl inches, and provided with round'holes of approximately a half inch diameter across about ten inches of its width. The outer strip 15 would, of course,

'be made somewhat narrower than the strip 10 and composed of eighteen gage metal its holes-might desirably be one-half inch long and one thirty-second inch wide with.

approximately 45% of the metal cut away. The wire-cloth screen 14 could b e of any suitable finer mesh or gage and of course would be of a width to cover the' holes or perforationsbf the two spiral metal sheets between which it is held. v

In actual practice tubes of standard andA ordinary size7 are made ,up of the single sheet 10 andA kept in stock. Upon order,

such mainrsupporting tubes are supplemented by or tted'with the spiral perforated sheet 15 with holes of the. required size, and if a still finer mesh is required a sheet 14 of the wire-cloth screen is interposed between and held in -`position by the other two.

The .spiral orghelical sheet 10,j ofcourse, constitutes the main `body of the tube or pipe and is made .of metal of suiicient thickness to withstand the usual strains and stresses. The smallness of the sizes of theloles which may be punched in such sheet is strictly limitedas explained above and --when a lfinerl mesh of tube is needed these holes must besupplemented with others of smaller size.

By arranging the slots in the outer metal essence of the invention and without the'sacriice of any of its substantial benefits and advantages.

s. I claim:

1. A well-screen of the character dei scribed, `comprising in combination a tube composed of a sheet of metal with a smooth' outer surface bent to spiral form having a series of perforations intermediate its edges andits one longitudinal marginal portion outwardly overlapping the opposite longitudinal marginal portion of the sheet and secured thereto, the edge of the outer overlapping part forming .an exterior upwardlyfacing spiral shoulder, and a second sheet of l metal bent into spiral form around said vfirst sheet and secured thereto and having apertures therethrough of a size different from those of said first sheet, substantially as described. i.

2. A lwell-screen of the character described, comprising in combination a tube composed of a sheet of metal with a smooth outer surface bent into spiral form having a series ofperforations intermediate its edges and its one longitudinal marginal portion outwardly overlapping the lopposite longitudinal marginalportion of the sheet and secured thereto, the edge of the outer overlapping part forming an exterior upwardlyfacing spiral shoulder, and a second thinner sheet of metal bent into spiral form around said first sheet and secured thereto and having apertures therethrough of a size and shape different from those of said first sheet,

-substantially as described.

3. A. well-screen of the character described, comprising in combination a tube composed of a sheet of metal with a smooth outer surface bentinto spiral form having a seriesl of round perforations intermediate its edges and its one longitudinal marginal portion outwardly overlapping the opposite longitudinal marginal portion of the sheet and secured thereto, the edge of the outer overlapping part forming an exterior upwardly-facing spiral shoulder, and a second thinnersheet of metal bent into spiral form around and secured to said first sheet and having elongated holes therethrough with their longer dimensions disposed substantially parallel to the axis of the tube, substantially as described.

4. A well-screen of the character described, comprising in combination a tube composed of a sheet of metal with a smooth outer surface bent into spiral form having a series of perforations therethrough intermediate its edges and its one longitudinal marginal portion outwardly overlapping the opposite longitudinal marginal portion o f the sheet and secured thereto, the edge of Vtheouter overlapping part forming an exterior upwardly-facing spiral shoulder, and a second sheet of metal bent into spiral form v around and secured to said first sheet and having its lower edge substantially in contact with and protected by said spiral shoulder, said second sheet having apertures therethrough of a size different from those of said first sheet, substantially as described.

5,. A well-screen of the character described, comprising in combination a tube formed of a sheet of metal with a smooth outer surface bent into spiral form having a series of perforations therethrough intermediate -its edges and its one longitudinal marginal portion outwardly overlapping the opposite longitudinal marginal portion of the sheet and secured thereto, the edge of the outer overlapping part forming an eX- terior upwardly-facing spiral shoulder, and a second thinner sheet of metal bent into spiral form around and secured to said first sheet and having its lower edge substantially in contact with and protected by said spiral shoulder, said second sheet having apertures therethrough of a size and shape different from those of said first sheet, substantially as described.

6. A well-screen of the. character described,-comprising in combination a tube composed of a sheet of metal with a smooth outer surface bent into spiral form having a series of round perforations therethrough intermediate its edges and its one longitudinal marginal portion outwardly overlappino the opposite longitudinal marginal portior of the sheet and secured thereto, the I edge of the outer overlapping part forming by its exposed edge an exterior upwardlyfacing spiralshoulder, and a second thinner sheet of metal bent into spiral form around and secured to said first sheet and having its lower edge substantially in. contact with and L protected 'by said spiral shoulder, such second sheet having elongated holes therethroughwith their longer dimensions disposed substantially parallelto the axis of the tube, substantially as described.

7. A well-screen of vthe character described, comprisixig in combination'a tube composed-of a sheet of metal with a smooth outer-surface bent into spiral form" having a series of perforations therethrough inten` mediate its edges and itsy one longitudinal marginal portion outwardly overlapping the opposite `longitudinal marginal portion of the sheet and secured thereto, the edge of the outer overlapping part forming by its exposed edge an exterior upwardly-facing spiral shoulder, a second sheet of metal bent into spiral formaround said first sheet and secured thereto and having apertures therethrough of a size different from those of said first sheet, and a spirally-disposed Wirecloth screen between said perforated metal sheets, substantially as described.

8. A well-screen of the character described, comprising in combination a tube composed of a sheet of metal with'a smooth outery surface bentv to spiral form having a Y series of perforations therethrough intermediate its-edges and its one longitudinal marginal portion Y outwardly overlapping the opposite longitudinal marginal portionl ,sheet having apertures therethrough of a size different from those' of said first sheet, and a spirally-disposed Wire-cloth screen between said perforated metal sheets, substantially as described.

9. A well-screen of the character-.de-

scribed, comprisingin combination a tubecomposed of a sheet of metal with a smooth surface bent into spiral form havinga series of round perforations therethrough intermediate the edges thereof and its one longitudinal marginal portion outwardly overlapping the opposite longitudinal marginal portion of the sheet and secured thereto, the edge of the outer overlapping part forming by its exposed edge an exterior upwardlyfacing spiral shoulder, a second thinner sheet of metal bent to spiral form around and secured to said first sheet and having its lower edge substantially in contact with and protected by said spiral shoulder, said second sheet having elongated holes therethrough with their longer dimensions 4disposed substantially parallel tothe axis of the tube, and a spirally-arranged wire-cloth screen of finer mesh than and positioned be-` tween said perforatedI metal sheets, fsubj 

